Pumping of liquids



March 30, 1943.

S. S. ALLENDER PUMPING 0F LIQUID Filed Dec. 18, 1939 12k/yf,

2 Sheets-Sheet 1 @flee @y f March 30, 1943.

S. S. ALLENDER PUMPING OF LIQUID Filed DeC. 18, 1939 2 Sheets-Sheet 2Patented Mar. 30, 1943 PUMPING OF LIQUIDS samuel s. Allende; New York,N. Y., assigner to Universal Oil Products Company, Chicago, Ill., acorporation of Delaware Application December 18, 1939, Serial No.309,755

1 claim.

The invention relates more specifically to an improved method and meansof absorbing shock and reducing the magnitude of pulsations in thedischarge line of a reciprocating pump due to the intermittent nature ofthe flow of liquid from the pump cylinder or cylinders. It is adaptableto the Ipumping of all volatile liquids or liquids having constituentswhich are readily vaporized and is particularly advantageous in :pumpinginflammable liquids and those to which the presence oi air may bedetrimental.

It is, of course, common practice to provide an expansion chamber on thedischarge line, manifold or outlet valve 'chamber of reciprocating pumpsto assist in absorbing.pulsations and minimize shock resulting from theintermittent nature of the pumping. action. Heretofore, such deviceshave merely provided an entrapped body of air which is compressed andexpands with variations in the pump discharge pressure and acts as acushion. In the present invention this air cushion is replaced by acushion comprising vaporized constituents of the liquid being pumped.This is accomplished by supplying suilicient heat to the upper portionof the expansion chamber to maintain a portion of the fluid in theexpansion chamber in vaporous state.

Heating of the expansion chamber and vaporization therein may beaccomplished, for example, by providing a closed coil within or a jacketor coil about the upper portion of he chamber and circulating a suitableheating medium therethrough. In case the pump is driven by-steam orother hot expanding gas, a portion thereof may be passed through thecoil 'or jacket to supply heat to the upper portion of the expansionchamber and maintain a vapor cushion therein. The heating medium in suchcases may be bled from the inlet or exhaust line of the pumping 4 theupper portion of the expansion chamber, particularly when the pump iselectrically driven and/or lwhen other heating means are not readilyavailable.

The use of a continuously maintained vapor cushion in place of an aircushion in the expansion chamber has numerous advantages, particularlyas applied to specific pumping problems. A

In addition to eliminating the d-angers which sometimes result from thepresence of air when combustible or inflammable liquids are beingpumped, the features of the invention obviate the possibility ofultimate practical elimination of the cushion in the expansion chamberwhen the pump is in continuous service over a prolonged period of time.For example, nearly all liquids will dissolve varying amounts of air andover a prolonged period of operation the air cushion in the 'pumpingcylinder may be thus dissipated. whereas with the present invention,although'va pors may also be dissolved from the cushion in the pumpingcylinder and/or condensed by the liquid present, the continuousapplication of heat causes the evolution of additional vapor to replacethat dissolved or condensed so that equilibrium conditions areestablished and a vapor cushion is continuously maintained, regardlessof the length of time during which the pump is continuously operated.

The accompanying drawings dlagrammatically illustrate several specificforms of apparatus, each embodying the features of the invention and inwhich the improved method of operation provided by the invention may. beaccomplished.

Fig. 1 illustrates a steam driven pump having an expansion chamberheated by steam supplied thereto from the inlet or from the exhaust lineof the steam end of the pump.

Fig. 2 is an enlarged longitudinal elevation shown partially incross-section, of the steam heated expansion chamber shown in Fig. 1.

Fig. 3 is a longitudinal elevation, shown partially in section, of amodified form of expansion chamber which may employ steam or 'other hotfluid as the heating medium.

Fig. 4 is an elevational view of an electrically driven reciprocatingpump having an electrically heated expansion chamber.

Fig. 5 is an enlarged elevational view, shown partially in section of aportion of the expansion chamber shown in Fig. 4.

Fig. 6 is an elevational view, shown partially in section, of a portionof a modified form of electrically heated expansion chamber.

Referring to Fig. 1, the reciprocating type of steam drii en pump hereillustrated has a steam cylinder I0 and a liquid pumping cylinder Ilinterconnected in the conventional manner, steam being supplied to thevalve chest I2 through line i3 and exhausted therefrom through line i4.

The liquid to be pumped is supplied to the valve chamber of the iiuid.end of the Dump through suction line I5 and directed therefrom throughdischarge line I6. The expansion chamber Il\communicates with dischargeline I6 and a closed coil I8 is provided in the upper portion of theexpansion chamber. Steam may be supplied to coil I8 from the inlet steamline I3 through line I9 and valve 20 or exhaust steam from line I4 maybe supplied to the coil through line 2|, valve 22 and line I9. Steam andany condensate formed in coil I3 are discharged therefrom through line23 and valve 24. Valves and 22 are block valves and valve 24 isregulated to maintain the desired ilow of steam through the coil.

Exhaust steam may be utilized in coil I8 when its temperature issuiiicient to maintain a substantial portionof the liquid being pumpedin vaporous state in expansion chamber I'I and when the back pressure inthe exhaust steam line is sufficient to force steam through the coil atthe required rate. In other instances, live steam from line I3 may beemployed.

Referring now to Fig. 2, to facilitate the insertion of coil I8 in theupper portion of the expansion chamber and facilitate its removal forinspection and repair, whenever necessary,

the upper head of the chamber is a flanged bonnet removably bolted tothe flanged substantially cylindrical lower portion oi the chamber asindicated at 26. Packing glands 21 are provided in bonnet 25 throughwhich the inlet and outlet ends 28 and 29, respectively, of coil I8extend.

Referring now to Fig. 3, the expansion chamber here designated by thereference numeral 30 of conventional form, except that a jacket 3| isprovided at its upper end and spaced from the walls 32 of the chamber.Steam or other hot fluid of sutdcient temperature to maintain asubstantial portion of the iiuid Within the expansion chamber invaporous state is admitted to the space 33 between jacket 3I and theupper portion of walls 32 through line 34 and after transferring heatthrough Walls 32 to the fluid Within. the chamber, the spent orpartially spent heating medium is discharged from space 33 through line35.

With a pump driven by an internal combustion engine, the arrangement maybe substantially the same as illustrated in Fig. l, except that anexpansion chamber of the general type shown in Fig. 3 is preferablyemployed and only the combustion gas exhaust line, corresponding to lineI4 of Fig. l, is connected with the steam jacket of the expansionchamber through line 34, which replaces lines 2I and I9. No valve willordinarily be required in this line but a regulating valve` preferablyof the gate or butteriiy type, may be employed in the outlet line 35from space 33 in the same manner as valve 24 is employed in Fig. 1.

An expansion chamber of the general form shown in Fig. 3 may besubstituted, in Fig. i, ior the type shown in Figs. 1 and 2 and ispreferably employed when exhaust steam is utilized as the heating mediumsince it may be designed to offer less resistance to the iiow of steam.

Referring now io Fig. 4, the reciprocating pump here illustrated is ofconventional form except for the heating means provided in the upperportion of the expansion chamber 40. A motor 4i. supplied withelectrical energy through lines 42, is connected through pinion 43 withgear 44 and pitman 45 connects gear 44 with piston rod 46.

The valve chamber 4'I of the pump is mounted above the pumping cylinder48, the inlet line for the fluid to be pumped communicating with thevalve chamber on the opposite side of the pump from that hereillustrated. The discharge line which communicates with the valvechamber is indicated at 49.

Expansion chamber 40, in the particular case here illustrated, isintegral with bonnet of the valve chamber and an immersion typeelectrical heating unit 5I is provided in the upper portion of chamber40. Electrical energy is supplied to heater 5I through lines 52 fromlines 42, which supply electrical energy to motor 4l, and a suitableswitch indicated at 53 is provided in one of the lines 52.

Fig. 5 illustrates how the immersion type heating element 5I may beinserted into the upper portion of chamber 40 through a threaded port 54at the upper end of the chamber, the upper end of rod 5I being threadedto engage the threads of the port and seal the chamber. Resistance wires55 of heater 5I are electrically insulated from the metal outer walls ofthe latter, preferably by a heat conductive material such as for examplemagnesium oxide, porcelain or the like, not illustrated.

The expansion chamber shown in Fig. 6 may be substituted for chamber 40of Figs. 4 and 5 and is similar thereto except that instead of providingan internal or immersion type heating element, theheating element isdisposed about the exterior surface oi the upper walls of the chamber.The heating element of chamber $0 comprises resistance Wires 6I encasedin a substantially rigid body 62 of electrical insulating, heatconductive material such as magnesium oxide, for example. ResistanceWires 6I form a coil which is connected at its opposite ends toterminals 63 to which conductor wires 64, form a suitable source ofelectrical energy, are also attached. The rigid molded shape 62 conformsto the contour of the upper portion of the walls of chamber 60 and isencased in suitable heat insulating material 65.

It will be understood, of course, that it is within the scope of theinvention to employ an electrically heated expansion chamber with pumpsdriven by steam or other expanding hot gases and also that an expansionchamber heated by steam or other hot iiuid may be employed onelectrically driven pumps. Many speciiic forms of electrically heated orfluid heated expansion chambers, other than the specific formsillustrated, are, of course. also Within the scope of the broaderaspects of the invention.

I claim as my invention:

In combination, a iiuid pump driven by an electrical power means, leadsconnecting said power means with a source of electricity, moans forequalizing the pulsations of said pump comprising a chamber mounted inthe discharge line of said pump, means for heating said chambercomprising a casing mounted on the outside o said chamber, heatconducting electrical insu' `ting material within said casing,resistance ele.. ents in said casing mounted within said mateijh'l. andmeans for connecting said resistance "Ielemenis with said source ofelectricity.

SAMUEL S. ALLENDER.

